Storwize V3500 overview

Each IBM® Storwize® V3500 system is a virtualizing RAID storage system.

Storwize V3500 machine code

IBM Storwize V3500 is built with IBM Spectrum Virtualize™ machine code, which is part of the IBM Spectrum Storage™ family.

The system also provides these functions.
  • Large scalable cache
  • Copy Services
    • IBM FlashCopy® (point-in-time copy) function, including thin-provisioned FlashCopy to make multiple targets affordable
    • Data migration
  • Space management
    • Metering of service quality when combined with IBM Spectrum Control Base Edition. For information, refer to the IBM Spectrum Control Base Edition documentation.
    • Thin-provisioned logical volumes

Storwize V3500 hardware

The Storwize V3500 storage system consists of one drive enclosure. The enclosure contains disk drives and two node canisters.

Figure 1 shows a Storwize V3500 system as a traditional RAID storage system. The internal drives are configured into arrays. Volumes are created from those arrays.

Figure 1. Storwize V3500 system as a RAID storage system
This figure shows an overview of a RAID storage system.

The two node canisters are known as an I/O group. The node canisters are responsible for serving I/O on the volumes. Because a volume is served by both node canisters, there is no loss of availability if one node canister fails or is taken offline. The Asymmetric Logical Unit Access (ALUA) features of SCSI are used to disable the I/O for a node before it is taken offline or when a volume cannot be accessed via that node.

Volumes types

You can create the following types of volumes on the system.
  • Basic volumes, where a single copy of the volume is cached in one I/O group. Basic volumes can be established in any system topology; however, Figure 2 shows a standard system topology.
    Figure 2. Example of a basic volume
    This figure shows an example of a basic volume in a standard system configuration.
  • Mirrored volumes, where copies of the volume can either be in the same storage pool or in different storage pools. The volume is cached in a single I/O group. Typically, mirrored volumes are established in a standard system topology.
    Figure 3. Example of mirrored volumes
    This figure shows an example of a mirrored volume in a standard system configuration.

System management

The Storwize V3500 nodes operate as a single system and present a single point of control for system management and service. System management and error reporting are provided through an Ethernet interface to one of the nodes in the system, which is called the configuration node. The configuration node runs a web server and provides a command-line interface (CLI). The configuration node is a role that either node can take. If the current configuration node fails, the other node becomes the configuration node. Each node also provides a command-line interface and web interface for performing hardware service actions.

Fabric types

I/O operations between hosts and Storwize V3500 nodes and between Storwize V3500 nodes and RAID storage systems are performed by using the SCSI standard. The Storwize V3500 nodes communicate with each other by using private SCSI commands.

Table 1 shows the fabric types that can be used for communicating between hosts, nodes, and RAID storage systems. All installed fabric types can be used at the same time.

Table 1. Storwize V3500 communications types. Summary of communication types that are used by Storwize V3500
Communications type Host to Storwize V3500 Storwize V3500 to storage system
Fibre Channel SAN Yes, with Fibre Channel host interface adapter Yes, with Fibre Channel host interface adapter
iSCSI (1 Gbps Ethernet) Yes No